Effects Of Exogenous Gangliosides Research Articles

Effects of exogenous gangliosides on intracellular Ca2+ mobilization and functional responses in human platelets.

Gangliosides, highly expressed in the outer leaflet of plasma membranes, mediate a variety of biological processes, including cell-cell and cell-matrix interactions. We examined the effects of exogenous gangliosides on intracellular Ca2+ mobilization and functional responses in human platelets. Gangliosides (GM3 and GM1) induced rapid and reversible elevation of intracellular Ca2+ in fura2-loaded platelets in a concentration-dependent manner. The Ca(2+)-mobilizing effect of gangliosides was not mimicked by deN-acetyl-GM3, lactosylceramide, or free sialic acid, suggesting that structural integrity as ganglioside is essential for this effect. GM3 and GM1 also induced platelet shape change by themselves and elicited aggregation in combination with epinephrine. Our observations suggest the involvement of ganglioside-activated platelets in atherosclerosis, in view of the high observed ganglioside levels in atherosclerotic lesions of human aorta.

Cell surface distribution of endogenous and effects of exogenous gangliosides on neuronal survival, cell shape and growth In vitro

In vitro immunostaining of neurons from spinal cord or brain of embryonic chicken by means of monoclonal anti-ganglioside antibodies (Q211, D21b) revealed a fluorescence-labeling of c-polysialogangliosides and GD1b evenly distributed over the entire neuronal surface including filopodia at the growth cones. On electronmicroscopical level the gold-stained ganglioside-antigens were found more or less densely packed in small adjacent areas suggesting a concentration in local “domains”. Survival in serum-free or serum-containing medium of embryonic spinal cord motoneurons, which normally died if not cultivated in muscle conditioned medium or in contact to myotubes, was remarkably improved in the presence of a ganglioside mixture (10 μM) from bovine brain. If embryonic neurons from optic lobes were cultivated at low Ca 2+-concentration (<20 μM) they developed flat, broad cell bodies with many filopodia and only a few flat-shaped short processes. A very weak cytoskeleton-staining by means of rhodamine-linked phalloidine indicated that polymerization of actin was impaired in these neurons. At the same low Ca 2+-concentration of <20 μM but in the presence of ganglioside GM1 (up to 100 μM) most of the neurons developed a “normal” cell shape with rounded perikarya and thin neurites with “normal” shaped growth cones. In this case rhodamine-linked phalloidine revealed a much more intense staining mainly concentrated within the growing tips. The morphology and growth of the ganglioside-treated neurons resembled that of neurons cultivated at a higher Ca 2+-concentration of at least 600 μM.

Differences in neuronal lipid composition between superior cervical ganglia and nodose ganglia of the rat

The lipid content and composition of rat superior cervical ganglia containing sympathetic motor neurons and nodose ganglia containing parasympathetic sensory neurons were studied for the first time to elucidate the mechanism of the different effects of exogenous gangliosides on these neurons in the culture medium. The ganglioside content of the superior cervical ganglia was almost 3-times that of the nodose ganglia. Although both ganglia contained G M3, G D3, G D1b and G T1b as major gangliosides, the nodose ganglia additionally contained a significant amount of sialosyllactoneotetraosylceramide L M1 (10% of total sialic acids). Contrasting with nodose ganglia, vagus fiber and dorsal root ganglia of rats, superior cervical ganglia had a higher content of sulfatide than galactosylceramide. The phospholipid content was lower in superior cervical ganglia than in nodose ganglia. Superior cervical ganglia contained less ethanolamine plasmalogen and more phosphatidylcholine than nodose ganglia. Sphingomyelin in superior cervical ganglia contained mainly medium-chain fatty acids, while that in nodose ganglia contained mainly longer-chain fatty acids. Differences in the fatty acid composition of glycerophospholipids were also observed. The results indicate that the properties of neuronal cell membranes from superior cervical ganglia and nodose ganglia are quite different, and that the differences may reflect the physiological roles of these ganglia.

Enhanced sprouting of retinotectal fibers after early superior colliculus lesions in hamsters treated with gangliosides

The effects of exogenous gangliosides on sprouting of optic tract axons was studied in hamsters which, after a right tectal lesion on the day after birth (P1), had an abnormal retinotectal projection from the left eye to the left superior colliculus (SC). Sprouting of these axons was induced by removing the competing input by right eye removal on postnatal day 9 (P9). Intraperitoneal GM1, given daily and started on P9, significantly stimulated the sprouting response. This was demonstrated by Fink-Heimer silver staining of anterograde axonal degeneration three days after the left eye was removed on P36. Terminal fields in the left SC were, in average, twice as large compared to controls. An estimate of the total number of terminals (silver stained particles) revealed a value of 7.9 X 10(6) for GM1 and 3.2 X 10(6) for control hamsters, respectively. Diencephalic structures which also receive collateral input from the sprouting optic tract did not show any alterations in the size of the terminal field due to GM1-treatment, suggesting that, in vivo, gangliosides fail to initiate sprouting in areas that have not previously been denervated. Unexpectedly, GM1-treated hamsters also had significantly smaller right SC damage and less left damage near the midline. Subsequent reanalysis of the data based on a lesion-matching procedure indicates that effects on reducing atrophy were independent of the GM1-enhanced sprouting of retinofugal axons. These findings provide the first direct evidence that exogenous GM1 stimulates lesion-induced axon sprouting in the mammalian brain.

Neural plasticity of basal forebrain cholinergic neurons: effects of gangliosides

Nucleus basalis magnocellularis (NBM) cholinergic neurons, furnishing the major portion of the extrinsic cholinergic innervation of the rat cortex, undergo specific retrograde changes in cell somata and choline acetyltransferase (ChAT) activity after cortical lesions. These are prevented in young and mature animals, but not in aged rats, by the chronic administration of exogenous ganglioside GM 1 after lesioning. However, a delay of 10 days (in young animals) in the commencement of treatment averted the responses to GM 1 in lesioned animals. It is suggested that the effects of exogenous gangliosides on retrograde biochemical and morphological alteration of cholinergic neurons may vary with circumstances permissive of plastic changes of central nervous system neurons at the time of administration.

Effects of exogenous gangliosides on proliferation and maturation of neurons in primary cultures

International Journal of Developmental NeuroscienceVolume 3, Issue 4 p. 458-458 Neurotrophic Factor and Metabolic Aspect Effects of exogenous gangliosides on proliferation and maturation of neurons in primary cultures Michèle Durand, Michèle Durand Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this authorSuzanne Harth, Suzanne Harth Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this authorDominique Lombard, Dominique Lombard Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this authorRaphaël Massarelli, Raphaël Massarelli Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this authorHenri Dreyfus, Henri Dreyfus Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this author Michèle Durand, Michèle Durand Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this authorSuzanne Harth, Suzanne Harth Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this authorDominique Lombard, Dominique Lombard Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this authorRaphaël Massarelli, Raphaël Massarelli Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this authorHenri Dreyfus, Henri Dreyfus Unite 44 inserm and cemtre de neurochimie du cms, 5 rue blaise pascal, 67084 Strasbourg cedex, FranceSearch for more papers by this author First published: 1985 https://doi.org/10.1016/0736-5748(85)90187-XAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume3, Issue41985Pages 458-458 RelatedInformation

Effects of exogenous gangliosides on morphology and biochemistry of neurons

Effects of exogenous gangliosides on morphology and biochemistry of neurons

Effects of exogenous gangliosides on the pattern of respiratory enzymes in experimental diabetic retino-pathy in the rat

The prevalence of LDH1 in the retina let us think that this tissue, in normal conditions, is particularly resistant to anoxia; yet the datum relative to the variations, of LDH1 pattern in the degenerating retina with decrease of LDH1, makes more probable the hypothesis of a variable sensitivity of the enzyme in the normal metabolic conditions. This consideration, which can also be extended to the other enzymatic systems, justifies our research line. 1. a) In the retina of hyperglycemic rat by Alloxan, LDH1 presents a progressive decrease of its activity up to reach values overlapping those observed in the degenerating retina; in rats pretreated with a gangliosides mixture this change does not occur; 2. b) also the degenerating-like increase of iso-enzyme 4 is undone by pretreatment with gangliosides; 3. c) The ATPase activities of hyperglycemic rat retina are also depressed in pretreated rats with gangliosides; While the relation between ATPase (Na + − K +) dependent activities and Mg ++ dependent activity remains depressed until 10th day of hyperglycemia, on the contrary, in the rats protected with gangliosides this relation becomes normal in 4th day; 4. d) The variations of MDH activity in the rat retina in experimental hyperglycemis do not appear statistically significant.